873NON-UNION IN FRACTURES.-THE MELANOMATA.

THE LANCET.

LONDON: SATURDAY, OCTOBER 24, 1925.

NON-UNION IN FRACTURES.THE factors influencing the normal growth of bone

are as yet imperfectly known ; still less reliable know-

ledge have we of processes essential for the union ofthe fracture of an adult bone. That general metabolicderangement has a potent influence, the existence ofbone changes in acromegaly and other diseases shows.It is therefore not surprising that unfavourable con-ditions of general health have always been held tocause delay in the healing of fractures. But innumerous cases of hindered union this factor can be

definitely excluded. The cause seems to be a localone.

A fortnight ago we published a lecture by Prof.E. W. HEY GROVES, who reviewed such causes, voicedhis own opinions, and gave advice as to treatment.He believes that one important cause of delayed unionis unrestricted mobility, and he makes a very importantdistinction between two forms of non-union. In theone the unifying process seems simply in abeyance ; thebone-ends, in X ray plates and if cut down upon,appear just to have remained unaltered from the time Iof the accident, whilst in the other there has been muchactivity of the bone-ends which have become sclerosedand eburnated, give a darker shadow with X rays, andare joined by dense fibrous tissue. The first varietywill often yield to non-operative measures, whilst thesecond calls for them. Prof. GROVES insists that properfixation is essential for union to take place. On this

point Mr. J. W. DOWDEN joins issue with him in aletter appearing elsewhere in this issue. In an expe-rience of 25 years he has but once met a fracture whichwould not unite, and that was of the clavicle, a resulthe attributes to having adopted the principle of mobilityin the treatment of fractures. It does not seem likelythat union would be favoured by free movements ofthe bone-ends on one another, a movement whichwould break down the adhesions between the opposinglayers of granulation tissue. A laparotomy woundwould certainly not heal if constantly dragged open.The granulation tissue bond must quite obviouslyremain intact for union to take place. This does notprohibit movements of surrounding muscles and neigh-bouring joints, and even a non-destructive bendingof the granulation tissue junction at the site of frac-ture. Such movements improve the local circulation,empty the clogged lymphatics, and generally promotethe healing process. Limited movements have provedtheir worth in the treatment of fractures. There isprobably no real conflict of opinion on the subject ofmobility, for the one surgeon advocates fixation ofthe fragments with movement of neighbouring jointswhilst the other in recommending mobilisation treat-ment insists that movements should be active incharacter and painless. A patient with a fracturecannot very well be induced to move his limb enoughto cause actual disturbance of the relation of the bonefragments to each other, for this provokes great painand by reflex muscle spasm limits the causative effort.

In spite of careful treatment surgeons do meet withcases of non-union, and Prof. GROVES’S classificationinto two types is of great practical importance. In theform in which cell activity fails, measures which furtherlocal nutrition should be instituted, a fact which

suggests that such non-union may depend upon injuryto the nutrient vessels occurring as part of the originalaccident. The slow repair after plating operationscan certainly be attributed to extensive stripping ofthe periosteum which sometimes is unavoidable. Whenfirm fibrous union with eburnated bone-ends occurs,an operation which removes the sclerosed tissues andopens up new paths for the osteoclasts becomes

necessary. This points to some barrier to the growthof osteoblasts across the interval between the frag-ments being present from the first, since bone forma-tion in the actual bone-ends is stimulated. Theobstruction can conceivably be intucked periosteum,which as MACEWEN showed opposes great resistanceto the through passage of bone-cells and possesses,in fact, bone-absorptive, as well as bone-formingproperties. Nothing but an open operation will removesuch an obstruction and allow the normal healingprocess to proceed. In the treatment of fractures bothfixation and movement have their place. To apportionthe right relative value to them, perhaps, would be tosay that fixation of the bone-ends is an essential,whilst movement of the surrounding soft parts. isdesirable.

THE MELANOMATA.THE suggestive fact emerges again and again that

the advances of morbid anatomy are often incom-patible with the most sacred dogmata of orthodoxbiology. Thus, the "law" of the "specificity ofthe germinal layers " decrees that, once these layersare formed in the embryo, they proceed in theirdifferentiation in certain directions only and give riseonly to certain kinds of tissue for which they are"predestined" by this law. When, for instance, theformation of mesenchyme by budding from theprimary germinal layers, the cells of which are of anepithelial habit, ceases, it ceases for ever. From nowonward the cells of the ecto- meso-, and endo-dermremain epithelial. We may well ask : Why shoulda process that takes place upon an extensive scaleduring the early stages of development necessarilyterminate at the precise moment at which it ceases.

to be observed by embryologists ? ‘? May it not be thatthe capacity is now merely latent normally but subjectto revival by the action of a pathological change It might be well for biologists, before they tell

pathologists that their education has been neglectedwhen they describe phenomena that are contrary to"

biological laws," to ask themselves if these " laws "

do not, perchance, require revision in the light ofpathological knowledge. There have been heterodox

biologists-to mention only MAURER, SCHUBERG, andmore especially RETTEREB,who claim that mesenchymeformation continues throughout life. It is to be fearedthat their writings are not much read. RETTERERinsists that practically the whole of the cutis is derivedfrom the epidermis by post-embryonic budding of its.cells.

Pathologists can, of course, form no authoritativeopinion of the merits or demerits of writings whichare concerned with the phenomena of normal growth,but there are many instances of abnormal growth ofan analogous nature which are within the provinceof pathology. The whole of the October issue of theEdinburgh Medical Journal is given up to a mono-graph 1 by Dr. J. W. DAWSON upon the melanomata,which is heretical and open to the severest disapproba-tion of orthodox biologists since he is unafraid to tell

1 The Melanomata ; their Morphology and Histogenesis. ByJames W. Dawson, M.D., D.Sc., F.R.C.P.E., Histologist, RoyalCollege of Physicians’ Laboratory, Edinburgh.